This is a multifaceted program consisting of five projects designed to increase our understanding of the monoclonal gammopathies. The projects in this program will increase our knowledge of the relationship between the various monoclonal gammopathies. Sera from patients with monoclonal gammopathies will be collected, typed, and stored in a freezing unit for further studies. Patients with monoclonal gammopathies will be followed in order to determine their course. Hybridoma techniques will be utilized to obtain monoclonal antibodies directed against plasma cell differentiation antigens. We also plan to develop monoclonal antibodies to plasma cell tumor markers. We plan to define the diagnostic and prognostic value of DNA S-phase measurements in patients with monoclonal gammopathies. Patients ranging from monoclonal gammopathy of undetermined significance to overt multiple myeloma will be studied with tritiated thymidine and 5-bromo-2-deoxyuridine monoclonal antibody methods in order to measure DNA S-phase values of plasma cells. DNA S-phase will be measured by surface marker features. The relationship of DNA S-phase of peripheral blood B lymphocytes and bone marrow T lymphocytes to disease activity will be examined. Results of these studies should lead to application of cell cycle kinetic measurements, to design of clinical trials, and to clinical practice. Serial chromosome studies will be performed on patients with multiple myeloma before treatment and during the course of their disease. In addition, chromosome studies will be done on cells grown in clonogenic cultures to determine if chromosome abnormalities occur only in plasma cells. Molecular studies will be done on all patients with a chromosomally abnormal clone. The molecular makeup of the site of chromosome breakage of any consistent chromosome abnormality in the expression of certain "oncogenes" will be performed. We will study the effect of melphalan-prednisone or colchicine or a combination of the three agents on patients with primary systemic amyloidosis (AL). These studies will provide information on patients with monoclonal gammopathies which is presently unavailable and may contribute to improved recognition, understanding, and management with patients with monoclonal gammopathies. (IP)